This market will resolve to 'Yes' if, by December 31, 2028, evidence of extraterrestrial life is presented, meeting the following criteria:

1. Publication in a Recognized Scientific Journal: The evidence must be detailed in at least one peer-reviewed publication in a high-impact scientific journal with significant academic reputation. Relevant fields include astronomy, astrobiology, or related scientific disciplines. Journals like 'Nature' and 'Science' are ideal examples, but other journals of similar standing are also acceptable.

2. Confirmation by Space Exploration Authorities: The evidence must be independently confirmed or endorsed by at least two reputable space exploration agencies or governmental bodies. Agencies that could fulfill this role include, but are not limited to, NASA (United States), ESA (European Space Agency), Roscosmos (Russia), CNSA (China National Space Administration), or ISRO (Indian Space Research Organisation).

3. Requirement for Direct and Unequivocal Evidence: The evidence must be direct and unequivocal, such as direct observations or physical samples, rather than indirect indications or substances presumed to be indicative of life.

The market will resolve to 'No' if, by the end of 2028, none of these criteria are satisfied. This includes cases where findings are published in recognized journals but lack confirmation by the specified agencies, or if confirmations are declared without an accompanying high-impact, peer-reviewed publication, or if the evidence is not direct and unequivocal.

Note: The market will resolve to 'Yes' if all the criteria are met at any time up to and including December 31, 2028.

Additionally, the evidence can pertain to either past or present extraterrestrial life, encompassing findings such as fossilized biological material or current life forms.

Updates

26th December 2023 - clarification concerning question in comments cection

Clarifications on 'Extraterrestrial Life':

• Discovery of a Single-Celled Organism on Europa: The discovery of a unique single-celled organism on Europa would count as a 'Yes', provided this discovery meets the publication and confirmation criteria outlined earlier. This discovery would be considered direct evidence of biological life beyond Earth.

• Discovery/Revelation of a Sterilized Non-Human Device: The discovery or revelation of a device of non-human origin, even if it demonstrates advanced technology, would not count as evidence of extraterrestrial life under this market's criteria. This market specifically seeks biological or organic evidence. Therefore, a technologically advanced but sterilized device, which provides no information about biological entities, would be categorized as a 'No' in this context. The focus is on direct evidence of living organisms or their biological remnants, not solely technological artifacts.

This "Update" clarifies that the market is focused on biological evidence, distinctly excluding technological artifacts unless they directly indicate the presence of biological life.